Photoelectric wall switch and relay system



June 27, 1967 H. R. SHAW ll PHOTOELECTRIC WALL SWITQH AND RELAY SYSTEMFiled Sept. 14, 1964 Tl!!! I ill!!! I 32 -P//0I'0 ca 1.

INVENTOR. Howard R. Shaw II I Fig.4. BY

United States Patent 3,323,592 PHOTOELECTRIC WALL SWITCH AND RELAYSYSTEM Howard B. Shaw H, 140 S. Belmont, Kansas City, Mo. 64123 FiledSept. 14, 1964, Ser. No. 396,328 Claims. (Cl. 25ii221) This inventionrelates to a photoelectric wall switch for controlling lights or otherelectrical apparatus without utilization of manually operated pushbuttons or the like.

It is an object of the instant invention to provide a photoelectric wallswitch which may be actuated even though the hands and arms areoccupied. Thus, when utilized in the home, for example, lights may beturned on or off while the householder is busyperforming household tasksor carrying items from place-to-place.

It is another object of this invention to provide a photoelectric wallswitch which also serves as a nightlight and eliminates fumbling in thedark when it is desired to turn on the lights.

Yet another object of this invention is to provide a switch as aforesaidwhich enables the operator to control the intensity of electric lightscoupled with the switch.

Other objects will become apparent as the detailed description proceeds.

In the drawing:

FIGURE 1 is a perspective view showing the instant invention mounted ona wall;

FIG. 2 is a vertical, cross-sectional view of the invention;

FIG. 3 is an electrical schematic diagram showing the circuitry of theinstant invention; and

FIG. 4 is an alternative circuit arrangement.

The numeral denotes a conventional electrical wall box mounted in a wall12. A light socket 14 is mounted within box 10 and has an incandescentbulb 16' in place therein. A cover plate 18 is secured to box 10 byscrews 20, plate 18 serving the usual decorative and protective functionin addition to mounting a beam splitter 22. A wall fixture 24 is spacedabove box 10 and mounted on wall 12 by any suitable means.

Wall fixture 24 is of generally L-shaped configuration as is clearlyillustrated in FIG. 2. A passage 26 is provided through the horizontalleg of fixture 24 which receives a conductor cable 28, the passage beingin regis-,

tration with an opening 30 in wall 12 permitting cable 28 to be coupled.with circuitry to be described hereinafter. A photoelectric cell 32 ismounted in the bend of fixture 24 in alignment with the light-receivingpassage 34 of an elongated, tubuluar hood 36 which forms the other legof fixture 24. Cell 32 is so disposed in the fixture that light raysentering the passage 34 in hood 36 and impinging thereon effectoperation of the cell to place the same in conduction.

Cover plate 18 has a central aperture 38 therein constituting alight-transmitting portion thereof in alignment with lamp 1-6. Plate 18is otherwise opaque. The beam splitter 22 includes an elongated, uprighthousing 40 of rectangular configuration having a lateral opening 42registered with aperture 38. A pair of upper and lower mirrors 44 and 46are mounted in housing 40- at angles of approximately 30 with thehorizontal for directing light rays from lamp 16 outwardly of housing 40through respective upper and lower, open ends 48 and 50 thereof. Thepassage 34 in hood 36 is longitudinally aligned with the path of travelof the light rays emanating from the upper end 48 so that such rays willimpinge directly upon cell 32. Rays striking the lower mirror 46 form anightlight as they pass downwardly through the lower end 50' "ice sothat the operator may conveniently locate the wall switch at night.

Referring to FIG. 3, it may be seen that cable 28 contains twoconductors denoted 28a and 28b, which conductors interpose photoelectriccell 32 in the circuitry shown. An alternating current supply source isconnected to terminals 52 and 54, a diode 56 being coupled in seriesbetween terminal 52 and conductor 28a. A resistor 58 connects the otherconductor 28b to a relay coil 60, the return for the coil being along alead 62 which is connected to terminal 54. An electrolytic capacitor 64is-connected across coil 60, diode 56, resistor 58, and capacitor 64forming a rectifying and filtering network for converting thealternating current into a direct current for utilization by relay coil60. In this manner, -a direct current relay may be employed.

Relay coil 60 is shown in its energized state and operates a singlepole, double-throw switch 66. A lead 68 from the lower contact of switch66 is connected to the relay coil 76 of a latch relay 72, the latterhaving a single-pole, double-throw switch 74 operably coupled with coil70. A capacitor 76 is connected in shunt relaionship to coil 70', lead78 being coupled with terminal 52 and serving as an AC return for coil70. Lead 78 is also connected to switch 74 and forms a part of the powercircuit to a load 84 connected to terminal 54, the remainder of thecircuit comprising a lead 82 interconnecting the other electrical sideof load 80 with the lower contact of switch 74. Connection points A, Band C are shown in FIG. 3 for the purpose of relating the portion ofthis circuitry extending leftwardly from these connection points with analternative arrangement shown in FIG. 4 and extending rightwardly of thepoints.

In FIG. 4, a stepper relay 84 is illustrated having a relay coil 86, aswitch element 88 coupled with coil 86, and four switch contacts 90, 92,94 and 96. The capacitor 76 is connected across connection points A andB, the latter being coupled with respective electrical sides of coil 86exactly in the same manner as shown in FIG. 3 for relay coil 70. In ananalogous manner, lead 78 is connected to switch element 88.

A resistor 2-8 is connected between switch contacts 92 and 94, and aresistor 1% is connected between contacts 94 and 96, the latter beingconnected to lead 82. Element 88 rotates in a clockwise direction uponenergi- Lzation of coil 86; therefore, upon repeated energization ofcoil 86, element 88 steps from contact to contact and varies theresistance in series betwen leads 78 and 82.

In operation, the housing (not shown) for the circuitry of FIGS. 3 or 4may be disposed at any convenient location between box 10 and fixture 24and the electrical load to be controlled by the apparatus. Bulb 16 isconnected directly across the AC line and operates continuously. Thisbulb may be a 7 watt lamp and thus is relatively inexpensive to operate.The hood 36 for the photoelectric cell serves to prevent ambient lightfrom affecting the cell, thereby eliminating the need for sensi tivitycontrols.

When the circuit of FIG. 3 is utilized, photoelectric cell 32 normallyremains in its conductive state and holds relay coil 60 energized. Thismaintains switch 66 out of engagement with its lower contact. When thelight rays in the path between the upper end 43 of housing 4d and thelower extremity of hood 36 are blocked by some obstruction, such as ahand or elbow, cell 32 changes to its nonconductive state and relay coil60 becomes de-energized. This engages switch 66 with its lower contactand permits current to pass along leads 62 and 68 to the coil 70 oflatch relay 72. In the illustration of FIG. 3, this would cause theswitch 74 of the latch relay to move into engagement with its lowercontact and remain in this position due to the operation of themechanical latch (not shown in detail).

The particular structural arrangement of the mechanical latch is notfully shown or described herein since such are conventional and widelyused in the art. Thus, it is apparent that the passing of an obstructionbeneath hood 36 causes momentary de-energization of relay coil 60, andmomentary energization of coil 70, to move switch 74 into engagementwith its lower contact and close the power circuit along leads 78 and 82to the load 80. Subsequent placing of an obstruction beneath hood 36causes an identical action except that switch 74 now returns to theposition shown and interrupts the electrical continuity in the powercircuit to load 80. In this manner, on-olf operation is achieved.

In the operation of the instant invention using the modified circuit ofFIG. 4, switch element 88 is advanced clockwise one position at a timeeach time an obstruction is passed beneath hood 36 to block the lightrays emanating from the upper end 48 of housing 40. FIG- URE 4 isespecially suited for operating lights in situations where it is desiredto have multiple light intensities which may be selected as desired.Initial movement of switch element 88 into engagement with contact 92places both of the resistances 98 and 100 in series between leads 78 and82 and thus constitutes the low position.

The next step of the relay places element 88 in engagement with contact94 and effectively bypasses resistor 98 to provide a medium position.The next step of the relay to place element 88 in engagement withcontact 96, bypasses both of the resistors and applies full voltage toload 80. Therefore, when the lights are initially off, it may beappreciated that the number of passes of an obstruction beneath hood 36controls the brilliance of the lights and that, once the high positionis reached, one more pass beneath the hood turns the lights off.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. Electrical control structure comprising:

a wall presenting an upwardly extending surface; and

switching apparatus on said wall accessible for operation thereof at aregion adjacent said surface, said apparatus including:

a housing in said Wall having a cover disposed substantially in theplane of said surface; a light source disposed in said housing, saidcover having a light-transmitting portion permitting radiation of lightrays from said source outwardly from the housing; a light-responsive,bistate device; a fixture on said wall spaced from said cover thereaboveand mounting said device in outwardly spaced relationship to saidsurface;

aaeea a light director on said cover registering with said portion andhaving a reflector for directing said rays along a first path of travelextending upwardly to said device, and a second path of travel extendingdownwardly whereby the rays in said second path form a night-light beamand the rays in said first path normally maintain the device in one ofits states and permit operation thereof to place the device in its otherstate upon blocking of the rays in said first path; and

circuit means coupled with said device and adapted for coupling with asource of electrical energy and a load, whereby to control energizationof the latter.

2. The invention of claim 1, wherein said light director includes anelongated, upright housing having a'lateral opening therein registeringwith said portion and upper and lower, open ends, said reflector beingmounted in said director housing for directing light rays enteringthrough said lateral opening upwardly through said upper end and alongsaid first path, and downwardly through said lower v end and along saidsecond path.

3. The invention of claim 1, wherein said fixture includes an elongated,tubular hood extending from said device toward said director, whereby tosuppress the effects of ambient light.

4. The invention of claim 1, wherein said circuit means includes a powercircuit for said load and latch relay means coupled with said powercircuit for successively interrupting and establishing electricalcontinuity therein in response to repeated operation of the device toplace the same in its other state.

5. The invention of claim 1, wherein said circuit means includes a powercircuit for said load having at least one series resistance therein, andstepper relay means coupled with said power circuit for successivelyinterrupting electrical continuity therein, establishing electricalcontinuity in the power circuit through said resistance, and effectivelydecoupling said resistance from said power circuit to apply full voltagefrom said electrical source to said load in response to repeatedoperation of the device to place the same in its other state.

References Cited UNITED STATES PATENTS 1,819,439 8/1931 Peterson317--124 X 2,039,604 5/1936 Miller et a1. 250-221 X 2,174,206 9/1939Etter 250221 X 2,228,780 1/1941 Roberts 250-221 2,363,145 11/1944Robbins 317l54 X 2,685,064 7/1954 Berger 2S0231 X WALTER STOLWEIN,Primary Examiner.

1. ELECTRICAL CONTROL STRUCTURE COMPRISING: A WALL PRESENTING ANUPWARDLY EXTENDING SURFACE; AND SWITCHING APPARATUS ON SAID WALLACCESSIBLE FOR OPERATION THEREOF AT A REGION ADJACENT SAID SURFACE, SAIDAPPARATUS INCLUDING: A HOUSING IN SAID WALL HAVING A COVER DISPOSEDSUBSTANTIALLY IN THE PLANE OF SAID SURFACE; A LIGHT SOURCE DISPOSED INSAID HOUSING, SAID COVER HAVING A LIGH-TRANSMITTING PORTION PERMITTINGRADIATION OF LIGHT RAYS FROM SAID SOURCE OUTWARDLY FROM THE HOUSING; ALIGHT-RESPONSIVE, BISTATE DEVICE; A FIXTURE ON SAID WALL SPACED FROMSAID COVER THEREABOVE AND MOUNTING SAID DEVICE IN OUTWARDLY SPACEDRELATIONSHIP TO SAID SURFACE;